Some 2.4 million people in the U.S. have used heroin at some point in their lives.

About 4.5 percent of a nationally representative sample of U.S. adults have reported non-medical use of prescription opioids—12.9 percent of them abused opioids.

Heroin use in the United States has remained at high levels since the mid 1990s, with more than 100,000 new users annually.

About two thirds of people who use heroin also use prescription opioids, which are most commonly obtained from relatives, friends, or dealers.

Heroin has a duration in the body of four to five hours.

What are the warning signs?

According to Dedham Police detectives, the following are common signs that people might be abusing drugs.

•Change in friendships;

•Lack of physical hygiene;

•Behavioral and emotional changes;

•Changes in sleeping and eating patterns;

•Missing school and work, or losing a job;

•Withdrawal from family members;

•Items missing from the house;

Changes in people’s level of consciousness and emotional ability, lack of self-care, financial problems, and poor functioning at work and at home, according to Dr. Dennis Teehan, Jr.

If you believe you or someone you know has a problem, call detectives Bob Walsh or Kevin Mahoney at 781-326-1212 or 781-751-9301.

Dedham Police also have an anonymous tip line—781-326-7666—people can call.

Where can someone get help?

Here is a list of a few of the multiple programs that aim at helping people struggling with addiction and/or their families.

Alcoholics Anonymous (AA): A free support group for people struggling with addiction. Attendees typically share their experiences and hope to recover from alcoholism. For locations and times, visit www.alcoholics-anonymous.org.

Narcotics Anonymous (NA): A community-based organization that offers a 12-step recovery program for drug addicts. For more information, visit www.na.org.

Teen Challenge USA: A 12-month Christian program that encourages participants to cope with everyday life issues, by reading the Bible, participating in recreational activities and working on projects. For more information, visit teenchallengeusa.com.

Al-Anon: A support group for friends and family members of alcoholics and drug addicts. For information on meeting times and locations, visit al-anon.alateen.org.

Nar-Anon: A 12-step program for friends and family members of drug addicts. For meeting locations, visit www.nar-anon.org/naranon.

Learn to Cope: A free peer-led support network for parents and family members who have a loved one struggling with addiction. For more information, visit learn2cope.org.

Massachusetts National Alliance on Mental Illness: A website that provides extensive information for people and families facing mental illnesses, including substance abuse. For a complete list of substance abuse treatment centers, recovery community organizations, and information on addiction, visit www.namimass.org/resources/substance-abuse.

Editor’s note: This story runs in conjunction with a separate piece about the town’s reaction.

Ron Brock knew he had a problem. The first sign of trouble were the polymorphic overdoses. Then he started stealing from drug dealers and bunking in an abandoned house in Dorchester.

But it wasn’t until Aug. 10, 2004, that the 41-year-old Dedham native sought help.

"I robbed a drug dealer that night, and at that point I knew that my end was very close. I could hear a word in my head going over and over: The axe is at your root," Brock recalled while sitting in a high-top table at a coffee shop. "And so I knew that my time was very limited. I had many drug overdoses. I was going to kill someone and go to prison for life, or someone was going to kill me."

Brock got in a car late that night and he drove from his dealer’s house in Brockton to his father’s in Dedham to tell him: "I can’t live this life anymore. I need help."

At the time, Brock was using anything he could get his hands on including: Oxycodone; cocaine; heroin; alcohol; and various forms of methamphetamine, he said.

With the help of his father and sister, Brock enrolled in Teen Challenge, a 12-month program for people struggling with addiction. He stayed in the residential program for 21 months.

Brock, now 50, hasn’t used drugs in almost 10 years. He works fulltime at RHC General Contracting and he is determined to combat the increase in drug use and overdoses in Dedham and nationwide.

A public health problem

In 2011, when the Dedham Police Department started differentiating overdoses from other medical calls, dispatch received at least 30 calls for overdoses, 38 in 2012, and 41 last year, including five that were fatal, according to Detective Kevin Mahoney.

Since January, police have responded to 15 overdoses, including seven in March, Chief Michael d’Entremont said. Of those, at least five were treated with Narcan, an intranasal drug commonly known by its generic name naloxone that is used to reverse the effects of opiate overdoses, he said.

"In 2013, three of the deaths, the information that we got is that they had just recently been out of rehab, a hospital, and then overdosed and deceased," d’Entremont said. "My understanding is that’s a common time when someone can overdose and pass away because their resistance has dropped and they go back to taking the same amounts as before. It’s a vulnerable time."

According to Detective Bob Walsh, addiction often leads to drug-fueled crimes, such as larceny, shoplifting, and housebreakings. He said at least half of the shoplifting incidents in Dedham are drug related.

The most common substances in Dedham, Mahoney said, include marijuana; heroin; opiates such as Oxycodone and Percocet; alcohol; and stimulants such as Adderall and Ritalin.

"I think the type of drugs that are abused change with the ages," Mahoney said. "Alcohol, anti-anxiety and depression (medications) are amongst adults. Certainly, the people we deal with the most are younger people because they are not (as) controlled."

Police have also come across other substances including cocaine, anti-anxiety drugs, and even Suboxone, a drug designed to help with opiate dependence, Mahoney said.

"By far the biggest issue that’s affected our community is the opiates: The Oxycodones and the heroin," Mahoney said. "The Oxycodones can be obtained legally or illegally through doctors, patients, pharmacies."

According to Dr. Dennis Teehan, Jr., medical director of urgent care and occupational medicine for Tristan Medical, the United States is facing an "epidemic" of opiate abuse.

Opioids—natural and synthetic substances with morphine-like activity—are commonly used to treat patients suffering from cancer and chronic pain, but opioid prescriptions for managing other pain have increased in the last 10 to 20 years, according to "Overview of the treatment of chronic pain" on UpToDate, a medical database.

Addicts, Teehan said, often start with prescription painkillers, then move to cheaper, more potent heroin.

Percocet 30, for example, costs about $30 on the street per pill whereas heroin can be as cheap as $4 a bag, or $40 for half a gram (10 bags), according to Norfolk County District Attorney spokesman David Traub.

"Heroin is very fast acting when it’s shot directly intravenously, so it gives a true high as opposed to a pill," Teehan explained. "An oxycodone, that’s designed for slow release."

"More people were dying and more people were addicted to prescription opiates than actual heroin," said Teehan, who is also a selectman in town. "It’s an epidemic. It’s literally killing tens of thousands of people a year, legally. I mean forget abuse of opiates. Even using opiates as prescribed is killing significant amounts of people.

"These are dangerous medicines with significant side effects, with significant risk of abuse, significant effects on the brain and central and peripheral nervous system. They are not to be taken lightly. These are serious, serious strong, powerful medicines."

The experimentation phase

Brock started experimenting with drugs at 12. Like many kids, he felt peer pressure to fit in, which meant smoking marijuana and drinking alcohol.

Page 3 of 4 - As his circle of new friends widened, so did his drug selection.

"That’s how my drug addictions all started because marijuana is just marijuana," he said, recalling his self-destructive path that lasted nearly three decades. "The next thing: It’s just a little coke. Oh, you’ve done coke; it’s just like coke—it’s crystal. You’re too hyper; you need to come down. Here’s some heroin. Here’s a Valium. And that’s today’s society, believe it or not. I see it in today’s kids all the time."

According to Brock, most addicts know they have a problem, but they think they can overcome it on their own. Others, he said, don’t know where to seek help.

"I knew I had a problem. I just didn’t want to accept it," said Brock. "My pride got in my way, and that’s with all of us addicts. We all know we have a problem. The problem is we don’t think it’s severe enough to go into a rehab or get treatment. What we believe is that we can do it on our own, and that’s when we say I’m going to quit this week. You quit for two weeks and the next thing you know you’re right back to doing it again."

When Brock left the rehabilitation center about seven years ago, he spent days at home afraid of going out and relapsing, he said. Brock felt lost after years of addiction, and he didn’t know where to seek guidance on how to adapt to his new lifestyle.

"I knew that I couldn’t get back out there, but I didn’t know what to do," he said. "(Addicts) are not educated on where to go, on how to stay away from drugs. We all know we have a problem. We don’t know where to look for help. I know where to look to get drugs, but I don’t know where to look to get help, where they’re not going to shun me or arrest me—that’s what most addicts are thinking."

Like Brock, Dedham resident Amy Thomas knows what addiction can do to people and their families.

For the Thomas’ family, the addiction spread like the flu. First it infected her eldest daughter, and then her other child.

"Everything changed," Thomas, 52, said. "She lost interest in school, her friends changed. She wasn’t coming home. She was being defiant. She stopped going to school."

Both of Thomas’ children were teenagers when they started smoking marijuana. They are now adults battling an opiate addiction, she said.

Page 4 of 4 - By senior year of high school, her daughter was doing cocaine and was placed in an 18-month rehabilitation and schooling program.

"She was out of control. The more we tried to control her, the worse it got," Thomas, a nurse at MetroWest Medical Center, said adding her daughter would disappear for three or four days at a time. "We took away the phone, took away the car, so the more we tried to control her, the worse her behavior got."

Drug addiction, Teehan said, usually starts with untreated mental health issues and a lack of social and community support. He said it takes time to get people off of opiates.

"If you have someone that is on a very high amount of opiate drugs and they abruptly stop, they’re going to get very sick," Teehan said. "They’re going to have tremendous pain in the withdrawal process. There are ways to get people off of opiates, but it takes time, it takes effort, and it takes resources, which aren’t always readily available."